As one of the technologies for suppressing influence of bit errors in a data transmission system, an error correction code has been widely in practical use. The error correction code is given, for example, at an end of data by a transmitter. A receiver can correct bit errors of received data using the error correction code.
In recent years, various error correction methods have been in practical use. The error correction methods are appropriately selected according to communication environment. As an example, when line quality is low, a method with a high correction capability is selected. Also when a low bit error rate is needed, a method with a high correction capability may be selected.
Note that an error correction control device that performs appropriate error correction control in accordance with change in an error rate is proposed (for example, Japanese Laid-open Patent Publication No. 3-71739). In addition, an error correction scheme for selecting an error correction method in accordance with line quality of a radio transmission path is proposed (for example, Japanese Laid-open Patent Publication No. 9-116486). Further, an error correction control method for preventing or suppressing data interruption at the time of changing error correction modes of a transmission system is proposed (for example, Japanese Laid-open Patent Publication No. 2013-13030).
In order to enhance error correction capability, for example, an error correction code having a long code length is used. In this case, a ratio of the error correction code to actual data increases, and therefore data transmission efficiency may be reduced. In addition, a time needed for an error correction process increases in a receiver, and therefore it may be difficult to provide services requiring high-speed response (e.g., securities transactions or exchange transactions).